It has been long time I reviewed eng-tips. Some good conversations are going on.
Caution for over-heating whenever an existing structure is involved. Provide shoring if you have to use a lot of welding.
Question is not clear but I think you are trying to design a monolithic footing which carries a wall flush on outside. If this is the case Analyze one foot strip of the monoslab taking into account of balancing interior slab as you would analyze a footing for eccentric load which becomes axial...
I found structural design and drafting software at www.eaglepoint.com I will check the strudl and the others.<br>
Also I came accros a program "spacegass" it is D&A program.<br>
I would like to thank to SHENOY for the help.